3GPP Specification Compliance for SMF Interfaces

This chapter covers the following topics:

Feature Summary and Revision History

Summary Data

Table 1. Summary Data

Applicable Product(s) or Functional Area

SMF

Applicable Platform(s)

SMI

Default Setting

Enabled – Always-on

Related Changes in this Release

Not Applicable

Related Documentation

Not Applicable

Revision History

Table 2. Revision History
Revision Details Release

First introduced.

Pre-2020.02.0

Feature Description

The SMF currently supports either the December 2018 compliance version of 3GPP specification or the June 2019 compliance version of 3GPP specification for the SMF interfaces such as N1, N2, N4, N7, N10, N11, N40, and Nnrf. The SMF processes the messages from these interfaces as per the compliance profile configured for the corresponding services. For information on the compliance profile configurations, see the Configuring Interfaces section.

Currently, only IE encoding and decoding is supported. The existing features work with the June 2019 specification versions. No additional features in the June 2019 version are supported.


Note

The SMF continues to support the older versions of 3GPP specifications and the compliance profile configuration controls the same for the SMF interfaces.


Standards Compliance

The SMF is one of the control plane (CP) NFs of the 5G core network. The SMF uses different interfaces to communicate with the other NFs or nodes. For example, the N4 interface exists between the SMF and User Plane Function (UPF). Each of the SMF interfaces comply to a specific version of the 3GPP specification depending on the compliance version supported.

Use the following table to determine the compliance mapping of each SMF interface and the 3GPP Standards specification versions.

Interface Relationship 3GPP Specification Version

N11

Between AMF and SMF

29.518

29.502

For December 2018 Compliance Support: 15.2.0

For June 2019 Compliance Support: 15.4.0

N7

Between PCF and SMF

29.512

For December 2018 Compliance Support: 15.2.0

For June 2019 Compliance Support: 15.4.0

N4

Between UPF and SMF

29.244

For December 2018 Compliance Support: 15.2.0

For June 2019 Compliance Support: 15.4.0

Nnrf

Between NRF and SMF

29.510

For December 2018 Compliance Support: 15.0.0

For June 2019 Compliance Support: 15.4.0

N10

Between UDM and SMF

29.503

For December 2018 Compliance Support: 15.2.1

For June 2019 Compliance Support: 15.4.0

N40

Between SMF and CHF

32.291

For December 2018 Compliance Support: 15.1.0

For June 2019 Compliance Support: 15.3.0

N1

Between UE and SMF

24.501

For December 2018 Compliance Support: 15.2.0

For June 2019 Compliance Support:15.4.0

N2/NGAP

Between RAN and SMF

38.314

For December 2018 Compliance Support: 15.2.0

For June 2019 Compliance Support:15.4.0

Configuring Interfaces

Use the following commands to configure the SMF interfaces in compliance with the 3GPP specifications.

configure 
   profile compliance profile_name 
      service 
         n1 version full version_format spec spec_version uri_version uri_version 
         n2 version full version_format spec spec_version uri_version uri_version 
         namf-comm version full version_format spec spec_version uri_version uri_version 
         nchf-convergedcharging version full version_format spec spec_version uri_version uri_version 
         nnrf-disc version full version_format spec spec_version uri_version uri_version 
         nnrf-nfm version full version_format spec spec_version uri_version uri_version 
         npcf-smpolicycontrol version full version_format spec spec_version uri_version uri_version 
         nsmf-pdusession version full version_format spec spec_version uri_version uri_version 
         nudm-sdm version full version_format spec spec_version uri_version uri_version 
         nudm-uecm version full version_format spec spec_version uri_version uri_version 
         range 
         ! 
         ! 

Important

Service selection is based only on the specification version. In future releases, the full API version will be used.


NOTES:

  • version full : Specifies the API full version for each service in the following format:

    <Major-version>.<Minor-version>.<patch-version>.[alpha-<draft-number>]

    The format is specified in 3GPP TS 29.501 V15.2.0, section 4.3.1.1.

  • version spec : Specifies the 3GPP specification version number. It can be one of the following values:

    • 15.0.0

    • 15.1.0

    • 15.2.0

    • 15.2.1

    • 15.4.0


    Important

    Configuring the 3GPP specification version value depends on the SMF interface. Not all the preceding versions are options for the SMF interfaces. Only a combination of the preceding versions exist as options for the 3GPP version compliance configuration. For details on the compliance version, see the Standards Compliance section.


    For example, to support 3GPP June 2019 specification compliance for the N7 (PCF) interface, configure the specification version as 15.4.0.

    The default version number depends on the SMF interface. For example, the default version is 15.2.0 for the N7 interface. Similarly, for the N10 interface, the default version is 15.2.1.

  • version uri : Specifies the API version URI for each service in the following format:

    "v" concatenated with a number

    It can be both v1 and v2, or either v1 or v2.

    For example, for the compliance version 15.4.0 in the NRF configuration for the service type nudm-sdm/nudm-uecm, mandate the configuration of the uri-version in the versions to ‘v2’. For compliance version 15.2.1, this configuration is optional.

    For example, version v1: (- url: '{apiRoot}/nsmf-pdusession/v1')

  • service : The service names as specified in 3GPP TS 29.510 V15.2.0, section 6.1.6.3.11.

Sample Configuration

The following is a sample output of the interface configuration:

product smf(config-compliance-comp1)# show full
profile compliance comp1
   service nsmf-pdusession
      version uri v1
      version full 1.0.0
      version spec 15.2.0
product smf(config-service-nsmf-pdu)# compliance-profile comp1
product smf(config)# show full-configuration profile smf
profile smf smf1
   service name nsmf-pdu
   --------------------------------------------------------------
   compliance-profile comp1
   --------------------------------------------------------------
!
!